PB1923: NON-HEMATOLOGIC AUTOIMMUNE DISORDERS IN CLL: PREVALENCE AND PROGNOSTIC IMPACT IN A REAL-LIFE COHORT FROM A SINGLE-CENTRE
Authors: Miguel Argüello De Tomás, Nil Albiol, Alba Mora, Paola Jara, Esther Moga, Josep Nomdedeu, Marta Pratcorona Canela, Maria Laura Blanco, Jorge Sierra, Carol Moreno
Journal: HemaSphere (2023)

Topic: 6. Chronic lymphocytic leukemia and related disorders - Clinical Background: Chronic lymphocytic leukemia (CLL) is marked by severe immune dysfunction, which results in an increased risk of autoimmune disorders (AID). The association of autoimmune cytopenia (AIC) with the disease has been extensively studied. However, there is little information about its relationship with other non-hematologic autoimmune complications. Aims: To describe the prevalence and characteristics of patients with CLL spectrum (CLL, small lymphocytic leukemia, and monoclonal B-cell lymphocytosis) and non-hematologic AID. The secondary objective was to ascertain differences in clinical and prognostic variables between AIC and non-hematologic AID groups. Methods: We included 712 patients with CLL from the historical database of our center. The medical records were retrospectively reviewed to identify any AID diagnosis. AID were categorized based on the American Autoimmune Related Diseases Association classification. Those patients with both AIC and non-hematologic AID were classified into the AIC group. Results: The main characteristics of patients with CLL and AID are shown in Table 1. After a median follow-up of 6.4 years (0.1-36.4), 87/712 (12.2%) presented non-hematologic AID, and 45/712 (6.3%) showed AIC; 11/712 (1.5%) had both AIC and non-hematologic AID. In the non-hematologic AID group, endocrine disorders were the most frequent (48.3%; 42/87), followed by dermatological AID (33.3%; 29/87; including 5 patients with paraneoplastic pemphigus), and other AID such as rheumatoid arthritis (6.9%; 6/87), vasculitis (5.7%; 5/87), and neuromuscular syndrome (6.9%; 6/87). Most patients (51/87; 58.6%) presented the non-hematologic AID, with a median time of 1.3 years (-45.8 – 15.9) before CLL diagnosis. We found a significant association between the presence of poor biological variables (i.e., unmutated IGHV), the need of antileukemic therapy, and the development of AIC. However, female sex was the only variable significantly associated with presence of non-hematologic AID and CLL. In terms of prognosis, patients who developed non-hematologic AID either before, at the time of, or after the diagnosis of CLL had significantly longer OS compared to those who developed AIC (13.9 vs 10.9; p=0.002). Summary/Conclusion: In our series, 12.2% of patients with CLL presented non-hematologic AID, being the most frequent endocrine disorder. The high prevalence of AID observed in this series was not associated with CLL adverse features and these patients had the same prognosis as those with CLL without autoimmunity. In contrast, the appearance of AIC was linked to the presence of poor biological features and had a negative impact on patients’ outcomes. The different characteristics observed between patients with CLL and non-hematologic AID and AIC may indicate different pathogenic pathways. Further studies are needed to clarify the underlying mechanisms of these phenomena.Keywords: Autoimmunity, Chronic lymphocytic leukemia, Prevalence, Survival